package main
import "fmt"

func main() {
	str:="hello, world"
	buf:=[]byte(str)

	for i:=0; i<len(buf)/2; i++ {
		j:=len(buf)-1-i
		buf[i],buf[j]=buf[j],buf[i]
	}


	fmt.Println(str)
	fmt.Println(string(buf))
}
